Niki jc ppt

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Transcript of Niki jc ppt

VITREOUS DETACHMENT AND VITREOUS OPACITIES

Nikhita Jacob, Third year

ANATOMY and PHYSIOLOGY

• Transparent, gelly-like• 4/5• 4ml• Anterior depression – hyaloid fossa or burger’s space• Periphery – dense cortex• Center – liquid • Viscosity

• Mechanical function – shape• Nutrients to lens and retina

Attachments

• Vitreous base – Ora serrata (4mm)• Behind lens- Hyaloid fossa (firm at young age)• Optic disc• Macula • Blood vessels

Vitreous components

• Refractive index • Water – 98%• Fine collagen fiblrils – cortex• Large amount – hyaluronic acid, amino acid,

soluble proteins, salts and ascorbic acid• Cloquet’s canal – 1-2mm wide• With age – volume of gel liquid content

Vitreous detachment

• Complete / partial• 3 forms: -Posterior -Anterior -Basal• Most common

Etiology

• Synchysis • Begins posteriorly – attachment undeveloped• Strong forces – anterior detachment and basal

detachment

Posterior vitreous detachment

• Separation – cortex from retina – posterior to base• PVD with synchysis and synersis – common above

65years• Common with senile liquefaction - Develops a hole

– hyaloid membrane – collects between membrane and internal limiting membrane of retina – PVD upto base with synersis of remaining vitreous gel

• More – aphakics and myopes

• Symptoms: - Flashes - Floaters - Decreased visual acuity - Cob-web like appearance - appearance of hair-like structure• Signs: - Biomicroscopic examination reveals - Synchysis - Weiss ring or Fuch’s ring – glial tissue

• Diagnostic criteria: - Requires examination of fundus - Ultrasound examination – vitreous

hemorrhage or lens opacification

Detachment of vitreous base and anterior vitreous

• Usual etiology – blunt trauma – anterior retinal dialysis – crystalline lens dislocation

• Complications: - Retinal breaks - Vitreous hemorrhage - Retinal hemorrhage - Cystoid maculopathy

• Treatment: - symtoms resolve – complete detachment - complications – treatment

Vitreous opacities

• Any relatively non-transparent structure – opacity – floaters

• Common conditions associated with vitreous opacity:

-Muscae vollitantes-Inflammatory vitreous opacity-Vitreous aggregates and condensation with

liquefaction-Amyloid degeneration-Asteroid hyalosis-Synchysis scintillans-Red cell opacities-Tumor cell opacities

Muscae vollitantes:• Physiological – residues – hyaloid vasculature• Fine dots and filaments• Drifts in and out of visual field

Inflammatory vitreous opacities:• Exudates – anterior/posterior uveitis• Pars planitis• Pan uveitis• Endophthalmitis

Vitreous aggregates and condensation with liquefaction:

• Commonest cause• Collagen fibrils – senile, myopic, post-trauma,

post-inflammation

Amyloid degeneration:• Amyloidosis• Amyloid material – thyroid, pancreas, heart,

vitreous• Bilateral

• Pathophysiology: -originates – retinal vessel walls – cloudy

margin• Symptoms: -Diplopia -Diminished vision• Signs: -External ophthalmoplegia -Vitreous opacities -Retinal hemorrhage -Exudates

Asteroid hyalosis:• Causes: -Genetic inheritance -Diabetes -Hypercholestrolemia• Pathophysiology: -Calcium containing lipid complexes –

collagen fibrils – throughout vitreous• Age: Elderly people• Sex: Both

• Symptoms: -Mostly asymptomatic• Signs: -Unilateral -Small, white rounded bodies – vitreous

gel – ophthalmoscopy• Treatment: - If vision affected – vitrectomy

Synchysis scintillans: (cholesterolosis bulbi)• Causes: - Degeneration condition - Damaged eyes – trauma, vitreous

hemorrhage or degenerative disease in past – end stage – pathogenesis unknown

• Symptoms: -Mostly asymptomatic

• Signs: - Small, white, crystalline bodies – cholesterol

accumulation. - Vitreous-liquid-crystals sink to bottom-

stirred up – eye movement -Beautiful shower of golden rain –

ophthalmoscopy

• Treatment: Not required.

Red cell opacities: vireous hemorrhage – leftouts of massive

vitreous hemorrhage

Tumor cell opacities: seen as free floating opacities –

retinoblastomas and reticulum cell sarcomas

Thank you